This invention relates to a method and apparatus for use in the separation of a dispersed contaminant phase from a phase mixture comprising the contaminant phase dispersed in a continuous fluid phase. The contaminant phase may be a solid, liquid, a gel or gas or any combination of these. Examples of contaminants are carbonaceous solids, metals and metal oxides (e.g., alumina fines), composites, water droplets, polymer chains and precipitates (such as wax crystals, asphaltenes, hot filtration sediment, and high molecular weight polar compounds). "Fluid phase" is used to indicate that the continuous background phase may be either a liquid or gas, liquid being the more usual. Examples of the application of this invention are the removal of particulate material, such as wax crystals, from a liquid stream or dispersed water droplets from lube stocks and other oils. Further possible applications of the invention are emulsion breakage, dehazing fuel oil, removal of fine particles from refinery process streams, particulate separation in coal liquefaction and oil shale processes, and removal of coagulated metal-rich fractions from residua.